Scrapers of generic kind for chain belts of twin inboard chain scraper conveyors are used particularly in underground mining operations and are subjected to high mechanical stress, since they have to convey the entire highly abrasive conveyor material in the conveying belt side of the scraper chain conveyor.
For example, DE 102 25 341 C1 discloses a scraper fixed on chain links of scraper chains whose horizontal and vertical chain links each consist of oval ring eyelet members with round chain bow ends. Fixing the scraper on the horizontal chain links of these link chains is carried out by means of a retaining or securing bracket which runs in one piece between the two insides of the scraper wings of the scraper bridge, clamps the horizontal chain links from below against the underneath of the head web of the scraper bridge and fits laterally by its bracket ends in grooves on the insides of the scraper wings. Mounting the retaining bracket is undertaken by vertically sliding in from underneath, and securing the bracket on the head web against release is carried out by means of spring pins which can be inserted in through bores, engage through the pivots which are formed integral on the upper side of the bracket and engage in corresponding bolt recesses in the head web.
From DE 195 11 043 C1 it is known that the horizontal chain links clamped on the scraper are exposed to increased wear if they are not clamped sufficiently firmly and permanently between the bracket and the scraper body. In order to counteract any loosening of the chain links on the scraper body during the moving conveyor operation, the chain brackets and the underneath of the scraper body are curved convex relative to the longitudinal axis of the scraper in order during assembly to exert a defined assembly force on the inner and outer arms of the chain links. This assembly force is introduced into the bracket via nuts and threaded bolts. The threaded bolts are formed integral on the upper side of the chain bracket and engage through bores in the scraper body. The nuts which are countersunk in large surface area sockets on the top side of the scraper body are screwed up tight by generating the assembly and clamping force thereon.
During operation of the scrapers with screw connections between the retaining brackets and scraper body, cracks appear in part in the scraper body particularly in the area of the recesses particularly when they are used in high performance conveyors. The cause of this is inter alia also the reduction in the cross-sectional size of the head web of the scraper bridge as a result of the recesses for the nuts. With the scraper known from DE 102 25 341 C1 this is indeed avoided by the comparatively strong pivots, but storing these retaining brackets as spare parts is however made difficult by the pivots, the material and manufacturing costs for both the brackets and the scraper bridge are high and in order to dismantle the retaining bracket it is necessary in order to prevent canting to act on the two pivots as far as possible simultaneously e.g. with a hammer tool.
The present disclosure is directed, at least in part, to improving or overcoming one or more aspects of prior systems.